1. Field of the Invention
The present invention relates to an enteral nutrition product for administration to a patient via a tube for nourishment, and more specifically to improvements in techniques for suppressing or reducing gastro-esophageal reflux that causes an administered enteral nutrition product to regurgitate from the stomach toward the esophagus of a patient.
2. Description of Related Art
Several approaches for feeding nutrition to patients are known. These approaches are classified as enteral feeding and transvenous feeding, according to the organ or region of the human body to which nutrition is fed. While enteral feeding is a procedure for administrating nutrition to the intestines, transvenous feeding is a procedure for administrating nutrition to blood flowing in the central or peripheral veins of a patient. Enteral feeding is classified into oral feeding and tube feeding, according to the route along which nutrition is fed from the outside to the inside of the body.
Oral feeding is conducted for a patient who can swallow food and allows such a patient to take food orally. Alternatively, tube feeding is conducted for a patient who suffers from dysphagia, by feeding nutrition to the patient's stomach or intestines via a feeding tube. Nutrition for administration by tube feeding is referred to as an enteral nutrition product. That is, tube feeding is a procedure for administering an enteral nutrition product to a patient via a tube, and it is classified into nasogastric tube feeding, gastrostomy feeding, and trans-intestinal-fistula feeding for feeding nutrition via a stoma formed in the intestines.
The above nasogastric tube feeding is conducted by intubating a feeding tube into the esophagus of a patient, with the feeding tube being open at one end positioned in the patient's mouth or nose, and then feeding an enteral nutrition product via the feeding tube into the stomach or intestines.
Alternatively, gastrostomy feeding is conducted by inserting a feeding tube through a stoma formed through the abdominal and stomach walls of a patient, and then feeding an enteral nutrition product from outside of the body to the inside of the stomach via the feeding tube. In addition, the above trans-intestinal-fistula feeding is a procedure to be conducted by inserting a feeding tube through a stoma formed through the abdominal and intestinal walls of a patient, and then feeding an enteral nutrition product from the outside of the body to the inside of the intestines via the feeding tube.
Japanese Publication No. JP2000-152975 discloses a conventional technique of administering an enteral nutrition product in the form of a fluid diet to a patient in a transnasal (i.e., via nose) or percutaneous (i.e., via skin) manner.
Japanese Publication for republishing in Japanese International Publication WO 00/13529 discloses a conventional technique of administering an anti-vomiting food which is made of a liquid solution containing a thickener, to a patient who is expected to undergo a transluminal (i.e., via a tube) administration of an enteral nutrition product in the form of a fluid diet, before, after or during the administration of the anti-vomiting food to the patient via a tube.
As for matters that demand attention in an attempt to administer an enteral nutrition product to a patient, suppression or reduction of gastro-esophageal reflux is referred to. The reason is that gastroesophageal reflux can be a cause of reflux esophagitis, aspiration pneumonitis, etc. While reflux esophagitis is an esophagitis resulting from the stimulation of the gastric acid within the contents regurgitated from the stomach, aspiration pneumonitis is pneumonitis due to the invasion of the regurgitated contents into the trachea.
The cardia has been formed in the stomach so as to function as a lid for preventing a gastric regurgitation toward the esophagus. In case of elderly people who require the above enteral feeding, in general, the function of the cardia is deteriorated, and however, even if the function of the cardia is normal, it is highly possible that gastro-esophageal reflux will occur. Therefore, when the administration of an enteral nutrition product to an aged patient is needed, the prevention of gastro-esophageal reflux is strongly demanded.
However, not only where a liquid enteral-nutrient but also where a fluid enteral nutrition product is used according to the disclosure of the aforementioned Japanese Publication JP2000-152975, gastro-esophageal reflux failed to be reduced adequately. As a result, a heavy burden was imposed on a caregiver for a patient.
FIG. 5 illustrates a model for explaining that, when a liquid or fluid enteral nutrition product is administered to a patient via a tube, there is a strong tendency for the enteral nutrition product to regurgitate from the stomach toward the esophagus. In FIG. 5, numeral reference 10 denotes the head of a patient, 12 denotes the feet, 14 denotes the abdomen, 16 denotes the back, 18 denotes the mouth, 20 denotes the stomach, 22 denotes the esophagus, and 24 denotes a liquid or fluid enteral nutrition product.
In addition, if the conventional technique disclosed in the aforementioned Japanese Publication for republishing in Japanese International Publication WO 00/13529 is practiced, it appears to be possible that both the fluid diet serving as the enteral nutrition product and the thickener, after being mixed together within the stomach of a patient, react with each other in a proper manner, and that, after a rise in viscosity of the contents of the stomach as a result of the reaction, gastro-esophageal reflux is reduced.
However, before the reaction between the fluid diet and the thickener occurs, both the fluid diet and the thickener are lower in viscosity. Thus, there arises a period of time during which the fluid diet and the thickener are stayed within the patient's body at a lower viscosity, and, as a result, it is highly possible that gastro-esophageal reflux will occur.
Therefore, even if the above-mentioned conventional technique is carried out, it is difficult to prevent gastro-esophageal reflux in an appropriate manner throughout the whole period of a process of administering the fluid diet and the thickener to a patient, ranging from the beginning to the end of the process.